Glow-worm energy saver 60 boiler-orange light not on?

This boiler suddenly stopped working, there have been no problems or indications, the orange light does now not come on. I have powered down and restarted to no avail, found and checked the 2 amp fuse. what is the significance of this orange lamp? Is there a reset button, I found a brown coloured component on the bottom of the electronics housing, but it doesn't move, is it a switch? how does it turn or should it press?
Any help would be appreciated